Several recent studies have demonstrated that central oxytocin and vasopressin pathways are important for species typical social behaviors in rodents. This proposal extends this work to non-human primates by investigating oxytocin and vasopressin in both normal and socially abnormal rhesus monkeys. Proposed studies will characterize the social and cognitive deficits in these monkeys, investigate the influence of centrally administered agonists and antagonists, and in post-mortem studies, assess oxytocin and vasopressin function with cellular and molecular techniques. As many of the behavioral deficits in these socially abnormal monkeys resemble the core features of autism and the deficit syndrome of schizophrenia, the results from the proposed studies may provide pathophysiologic insights and novel medications for these treatment-refractory syndromes.